Bad(no sound)problem in XP?

ok technically there is soudn.. a hissing noise typical to say speakers that have no song on but are switched on like a stereo but I'm talking about a headset but when i go into my computer/hardware/device manager/sound, video and game controllers my formerly there sound card's drivers are all just poof gone.. just legacy drivers there which are my onboard sound drivers. it had a yellow conflict but seemed to work although it was way too loud. and had a bug with windows management instrumentation awhile back but restored most of the issues. but when I started my comp but didn't type in my pword early enough it wouldn't load my sound drivers and it would all be greyed out in sounds and audio devices in Control Panel. I'm just intermediate if abit further but not a techy technically lol :P can anyone tell me what I can do? other than reformat as a last resort. but I would uninstall my sound drivers if it showed up in device manager but without doing that I risk loading them on top of my already existing folder and drivers which are just not s howing in device manager but show in that place before program files where windows is too.